Boxes on top are asymmetrical concession stands and bathroom along the walkway. Not sure why they did it this way, but it is what it is.

The best part about this addition is the change in acoustics in Tiger Stadium. The new upperdeck is directly across from the student section and band and act as an echo wall for those sound waves. It should make the loudest stadium in the country even louder by a significant margin, especially when considering the 7k more people and more tiger fans in the lower bowl (more visitors moved to upperdeck space).